Hrm... it's an interesting idea, but considering how the
IG recruit I don't understand how he'd get there... Maybe if he was a specialist or a normal trooper it'd be more probable.
But hey, nobody has a right to dictate to you on this stuff... Perhaps you could say they came accross him and found him resourceful? Made him an honourary member?
Maybe this
IG unit could have fought on the Squat homeworld?
Personally I'd use a figure like that for a rag-tag penal squad